for flows - AutomationChampion.com ( you can convert those scenarios to Trigger as well)
for apex fundamentals - Apexsandbox.io
for Trigger fundamentals - sfdc99.com
for trigger scenarios - / @sfdcninjas
for LWC - Zero to hero in lwc on udemy by salesforceTroop ( it as 2 courses, one just for projects)
for Integration - • Connect Postman to Salesforce for API...
Feel free to add more on this list via comments